1. Field of the Invention
The present invention relates generally to the detection and treatment of viral infection. More particularly, the invention relates to compositions and methods useful for the diagnosis of and vaccination against infection with a newly-discovered lymphotropic retrovirus, initially designated as feline T-lymphotropic lentivirus and presently designated feline immunodeficiency virus (FIV).
Domestic cats may become infected with several retroviruses, including feline leukemia virus (FeLV), feline sarcoma virus (FeSV), endogenous type C oncornavirus (RD-114), and feline syncytia-forming virus (FeSFV). Of these, FeLV is the most significant pathogen, causing diverse symptoms, including lymphoreticular and myeloid neoplasms, anemias, immune-mediated disorders, and an immunodeficiency syndrome which is similar to human acquired immune deficiency syndrome (AIDS). Recently, a particular replication-defective FeLV mutant, designated FeLV-AIDS, has been more particularly associated with immunosuppressive properties.
While immunodeficiency syndrome in cats has normally been associated with FeLV, immunodeficiency-like symptoms have been observed in cats which are seronegative for FeLV, usually without alternative explanation. It would be desirable to identify etiological agents other than FeLV which are responsible for causing immunodeficiency in cats. It would be particularly desirable to provide methods and compositions for the detection of and vaccination against such newly-identified etiological agents, and in particular, against FIV.
2. Description of the Background Art
The discovery of feline T-lymphotropic lentivirus (now designated feline immunodeficiency virus) was first reported in Pedersen et al. (1987) Science 235:790-793. Abstracts concerning the discovery of the virus were presented at the American Association for Cancer Research on May 23, 1987 (Abstract No. 3337) and at the Third International Conference on Acquired Immune Deficiency Syndrome, Jun. 1-5, 1987. A poster concerning discovery of the virus was presented at a meeting of the Federation of American Society for Experimental Biology on Apr. 2, 1987.
Characteristics of FIV have been reported in Yamamoto et al. (1988) Leukemia, December Supplement 2:204S-215S; Yamamoto et al. (1988) Am. J. Vet. Res. 49:1246-1258; and Ackley et al. (1990) J. Virol. 64:5652-5655. Cloning and sequence analysis of FIV have been reported in Olmsted et al. (1989) Proc. Natl. Acad. Sci. USA 86:2448-2452 and 86:8088-8092; and Talbott et al. (1989) Proc. Natl. Acad. Sci. USA 86:5743-5747.
Hosie and Jarret (1990) AIDS 4:215-220, describes the serological response of cats infected with FIV.
A portion of the experimental data presented in this application was published in AIDS 1990 4 (Suppl. 1):S163-S165.
Inactivated cell-virus and cell-free whole simian immunodeficiency vaccines have been reported to afford protection in macaques (Stott et al. (1990) Lancet 336:1538-1541; Desrosiers et al. PNAS USA (1989) 86:6353-6357; Murphey-Corb et al. (1989) Science 246:1293-1297; and Carlson et al. (1990) AIDS Res. Human Retroviruses 6:1239-1246). A recombinant HIV gp120 vaccine has been reported to afford protection in chimpanzees (Berman et al. (1990) Nature 345:622-625).